Circuit-breaker.



D. B. HUGHES.

CIRCUIT BREAKER.

APPLICATION FILED MAY 10. 1912.

1, 146, 1 67. Patented July 13, 1915.

5/ 52 v 4 H o UNITED STATES PATENT OFFICE.

DOW B. HUGHES, OF NEW YORK, N. Y., ASSIGNOR THECITIZENS SAVINGS AND TRUST COMPANY, or CLEVELAND, OHIO,

A CORPORATION OF OHIO, TRUSTEE.

CIRCUIT-BREAKER.

Patented July 13, 1915.

Application filed may 10, 1912'. Serial No. 696,335.

To allwhom it may concern: v

Be it known that 1, Dow B. HUGHES, a citizen of the-United States, "residing at New York, in the county of New York and State of New York, have invented a certain new and useful Improvement in Circuit-Breakers, of which the following is a I full, clear, and exact description.

This invention relates to circuit breakers or make and break devices adapted particularly for use with ignition apparatus, and has for one of its objects, the provision of a circuit breaker which has high efficiency and whichoperates as satisfactorily at the highest speeds at which the engine may be operated as at the lowest speeds.

Further, the invention aims to provide a circuit breaker having a construction such as to provide features of compactness, lightness, absolute control of the movements of the movable contact member, accessibility and ease of removal or adjustment.

Still further, the invention'aims to provide a circuit breaker wherein the electric.

contacts are inclosed within a compartment separate from that which contains the cam and cam operated part, and which are not liable to become fouled or clogged by dirt or oil, this latter feature being of particular utility in those ignition systems wherein it is desirable that-the contacts be separated only a small distance when the circuit is opened, and wherein the gap at the circuit breaker has a resistance which should be substantially invariable.

The above and other objects are accomplished by' my invention, which may be briefly summarized as consisting in.certain novel details of construction and combinations and arrangements of arts which will be described in the specification and set forth in the appended claims.

Although my present invention is not confined in its use to a magneto. lhave for convenience of illustration shown the circuit breaker in conjunction with a magneto, and in the drawings, Figurel is a side view of apor'tion of the magneto equipped with my improved circuit breaker,- a portion of the circuit breaker casing being broken away, so as to show the parts in the outer coinpartment of the circuit breaker casing; Fig. 2 is a sectional view, substantially along the line 2-2 of Fig. 1, looking in the direction indicated by the arrows, the section being taken through the circuit breaker and its inclosing casing; sectional view substantially along the line 33 of Fig. 2, looking in the direction.indicated by the arrows.

The magneto which may be designated as a whole by the reference character 10, is

and Fig. 3 is a transverse provided with an armature shaft or shaft extension 11, a portion of which is shown in Fig. .2, and the magneto wall is provided about the outer end of the shaft 11 with an outwardly projecting cylindrical extension 12, which constitutes a support or holder for the circuit breaker.

The circuit breaker includes a cylindrical member which .in effect constitutes a casing, and supports all parts of the circuit breaker except the cam. a telescopic connection with the cylindrical extension 152 and fits the latter so that the casing can 'be turned by the spark control mechanism or can be readily removed. This casing has between its ends a transverse dividing wall or partition 14 which divides the easing into an inner compartment 13 and an outer compartment 13", and the outer end of the casing is closed by a cap or disk 15 of fiber or other suitable insulating material.

Secured to the shaft 11 by a screw 16 or equivalent lever 18 pivoted by a pin 19 on The casing 13 has means is a cam 17 which rocks the wall Or partition 14. This lever carries.

erably formed of a pair of arc shapedplates between which member 20 is secured, and is thereforesufliciently light in weight to permit the cam engaging member 20 to be held at allctimes the cam engaging against the surface of the cam with very 1 little tension in the spring 21. The lever is provided with a laterally projecting in the partition 14, the outer end of the finger being located in coni partment 13 It will be noted that the lever 18 does not support and is connected neither directly nor indirectly to either of the electric contacts which are located, as ,will be explained, in a diflferent compartment than that which contains or receives the cam and lever. Consequently, the oil which it maybe .desirable to place on the surface of the'cam or to provide in the compartment 13 is not liable to reach or aflect the electric contacts in any way.

Secured to the partition 14, Within the compartment l3 by means ofscrews 23 or equivalent means, is an insulated block 24, which carries an adjustable screw 25, having at its upper end an electric'conta'ct 26. This contact 26 constitutes the normally stationary contact of the circuit breaker, and cooperating with this contact is a movable contact 27 which is carried by a light leaf spring 28 secured to a block 29 which in turn 1s secured to the partition 14. This spring 28 has an initial tension which presses the movable contact yieldingly against the relatively stationary contact. Both these contacts are preferably formed of platinum or other material which will not. easily wear or burn away. As will appear from Fig. 1, the end of the sprin 28 extends outwardly beyond the contact 2 over andin the path of movement of the finger 22, which is carried by a pivoted cam actuated" lever 18. The parts are so arranged that each time the lever is moved outwardly by the cam, this finger 22,. before the completion of the outward movement, engages and picks up the end of the spring 28, moving the contact 27 from the contact 26, and thence as the lever moves inwardly, the finger lowers the contact 27 onto the contact 26. Although thethrow ofthe lever 18 is not very great,

the spring 28 follows the movement of the finger only through'a portion of the movement of the latter. The degree of separation of the contacts 26 and 2 7 under the action of the finger 22 can be very nicely and accurately adjusted, by the adjustment of the screw 25, which has a fine pitch thread and can be locked in any position of adjust- .r'nent by a lock nut 25.

A feature of importance to be noted in connection with the part of the circuit breaker just described is the lightness of the spring 28, which supports the movable contact member 27.- It is due very largely to this feature-that the degree of separation of the contacts will be the predetermined amount, and will be no greater at high speeds than at low speeds, for the spring 28 will remain in contact with the finger, while the spring is being raised and lowered, and wil ,not be thrown outwardly or upwardly away from the finger, when the finger reaches .the upper limit.of its stroke, even though the finger is oscillated with. great-.'

rapidity. The casing which carries the principal parts ofthe'circuit breaker is provided on opposite sides with laterally proecting wings or arms 30, to,either of which the spark control mechanism may be attached. In advancing or retarding the spark, the casing of the circuit breaker and. all parts carried thereby are turned circumferentially with reference to the supporting The conductor which is c'onnected between the nuts 32 will be electrically connected to one end. of the armature winding of the I -magneto, and as the movable contact is grounded, by reason of the fact that it is connected to the block 29, which is in engagement with the walls of the casing,-

this contact will be electrically connected to the opposite end of the magneto winding.

It will be seen that by simply removing the end disk 15, the contacts of the circuit breaker are exposed to view, and are accessible for-ad ustment, 1f the latter is desired Also by removing the casing13, there is removed with it all parts of the circuit breaker, except the cam 17. The advantages of separating the parts of the circuit breaker in two separate compartments with the con-' 'tacts in one compartment, and the cam and its associated part in another compartment, have been previously brought out, and need not be further described.

Having thus described my invention,what I claimisz' 1. In a circuit breaker, a rotary cam, an arm adapted to be actuated by said cam, a

fixed and a relatively movable contact, a

support for the movable contact, means projecting laterally from said arm, and adapted to engage the support of said movable contact so as to cause said movable contact to be shifted from the stationary contact during a portion of the stroke of said arm.

2. In a circuit breaker, a rotary cam, a member adapted to be shifted by the cam, a pair of contacts including a stationary contact and a relatively movable contact, both displaced laterally with respect to said cam and member, a support for said movable contact, and means projecting from said member for engaging said support so as to cause a separation of the contacts.

In a circuit breaker, a casing, a cam, a (am-actuating shaft extending into the easing, an arm a'daptedto be shifted by said cam, a pair of cooperating contacts including a stationary contact and a movable contact, both displaced laterally with respect to the cam and located beyond the end of said contact operating means located on the, op-

- posite side of said wall, including a cam and a member movable thereby, said member having a part projecting through-said wall in operative relationship with one of the contacts. j

5. In a circuit breaker, a casing having a dividing wall 'so as to divide the casing into two compartments,- a stationary and a movable contact in one compartment, a rotary cam and a movable arm adapted to be rocked by the cam located in'the other compart ment, said arm having a fin er projecting through said wall so as to shi t the movable contact away from the stationary contact whensaid arm is moved outwardly from the In testimony-whereof, I hereunto aflix my signature in the'presence of two witnesses.

I DOW B. HUGHES.

- Witnesses: i

i A. F. Kw1s,

A. J. HUDSON. 

